Most outdoor lighting systems use some kind of photocontrol device to measure the amount of ambient light and turn the lights on and off accordingly. When it gets dark and the ambient light level drops below the specified threshold, the photocell sends a signal to turn the lights on. Then, when the sun comes back up, the photocell sends the signal to turn the lights back off.
However, most traditional photocells operate on currents only compatible with ballasted loads. If so, how do LED lights work with photocells, given that they’re much more sensitive to electric power fluctuations than fluorescent or halogen lights?
Do LED Lights Work With Photocells Designed for Traditional Lights?
In most cases, photocells designed for traditional lights use simple solid-state switching components to provide power to the lights. These components alter the wavelength of the AC current. Since they work on AC power, this change doesn’t affect tungsten and fluorescent lights. However, LEDs are much more sensitive to the changes in AC wavelength.
Since LEDs work on direct current, the light bulb needs to convert the current to DC first. A “clean,” uninterrupted AC signal can easily convert to constant DC. However, when the current goes through the photocell, the light bulb has much more trouble converting it to DC. This results in a noticeably dimmer light output than usual.
On top of that, the AC current might get so broken up that the bulb fails to output constant current to the LEDs. If so, you’ll notice your light constantly flickering. Such current wears out the LEDs extremely quickly, and their lifespan reduces significantly. If you notice your LED flickering when connected to a photocell, you should switch back to a traditional light as soon as possible.
So, do LED lights work with photocells? Yes, but first you need to make sure that the photocell you’re using is compatible with the LEDs. The best option is to go with an all-in-one solution, which combines lights, fixtures, and the photocell. In addition, you can find dimmable models, which enable you to fine-tune the lights’ intensity during dusk and dawn, keeping the light level constant throughout the day.
How to Determine If Your Photocell Is Compatible With LEDs
If you’d like to check if you can repurpose your current photocell from a traditional light source to LEDs, you need to consult its datasheet. In the rating specification, you’ll find all the lighting types it supports. Most traditional photocells are rated only for tungsten and ballast loads. If so, you’re better off buying a new photocell if you wish to switch to LEDs.
However, if you find the LED rating specified in the datasheet, you can just switch the light bulbs to LEDs. However, keep in mind that you need to stay under the maximum power rating stated in the datasheet. In addition, the photocell might have a separate power output for LED lights. If so, make sure you’re using that output, not the halogen/fluorescent power line.
Still, do LED lights work with photocells if they’re not included in the datasheet? Unfortunately, they usually don’t. In some cases, people have managed to make it work with some modifications. But even then, they always reported flickering issues and a shortened lifespan of the bulb.